Bus Tube
In electric arc bus tubes are secondary circuits carrying source current to water-cooled cables. Bus tubes are in fact thick copper pipes bended according to their design plan with threaded or clamped fitting on both ends connecting supply transformer to water-cooled cables’ bus.
Bus tubes are made of annealed (soft) ETP grade copper (ASTM C11000) or higher grade than OFC (ASTM C10100). Mentioned pipes and sections should be monolithic and weld-less and curves are created only by bending.
Also, all bended pipes must be hydro-tested or probed by radiography for leak or internal crack.
It should be noted that after production process, all the surfaces should be insulated through procedures mentioned in the induction furnace coil insulation and their electrical isolation must be maintained. For more info on this subject please refer to the insulation, coil insulation and induction furnace coil insulation material sections.